Blast attenuation container

ABSTRACT

A blast attenuation container, such as a litter bin or a container for storing explosive devices, is provided. The container includes an outer cover ( 22 ) defining an internal cavity and an inner receptacle ( 2 ) for containing litter or explosive devices. The gaining access to the internal cavity. The inner receptacle is lined with or formed from blast attenuation material for minimising the effects of a blast from an explosive device placed therein.

[0001] The present invention relates to a blast attenuation containerfor minimising the effects of an explosive device being detonated insidethe container.

[0002] Although the following description refers almost exclusively tolitter bins, it will be appreciated by persons skilled in the art thatthe present invention can relate to any container for minimising theeffects of an explosive device, being detonated inside the container.For example, the container can be a post box or a container forexplosives or pyrotechnics.

[0003] Litter bins are often targeted by terrorists for the location ofexplosive devices since the devices can be easily deposited and arehidden from view from security staff who are continually on the look outfor suspect packages. Once warning of a bomb threat has been delivered,the bomb threat area has to be evacuated and checked for suspectpackages. Litterbins are notoriously difficult to inspect since anydisturbance of the litter could potentially result in detonation of anexplosive device. This problem prolongs the inspection of the area andresults in great inconvenience to the people evacuated from the area. Italso increases the danger of the experts drafted in to find anddeactivate any explosive devices.

[0004] Unfortunately explosions have been detonated in litterbins andhave resulted in fatalities and serious injury to the public. Someconventional litter bins have been designed to reduce the force of ablast by incorporating hoop type formations of reinforced materialaround the perimeter of the same. A problem encountered with suchlitterbins is that whilst the hoops reduce the lateral force of theblast to some degree, they do not reduce the blast sufficiently toprevent injury to people. In addition, such bins will tend to drive theforce of the blast in the direction of least resistance, i.e., upwardly.Thus litterbins are not typically designed to reduce the vertical forceof a blast. Furthermore, although the force of the blast causes themajority of damage, explosion of the bin itself can result in damage andinjury due to lateral and vertical fragmentation; the fragments forminghigh speed projectiles.

[0005] It is therefore an object of the present invention to provide acontainer which attenuates the force of a blast detonated from insidethe same and which overcomes the abovementioned problems.

[0006] It is a further object of the present invention to provide acontainer which is inexpensive to produce, which can withstand the forceof a blast and which is aesthetically pleasing to the eye.

[0007] According to a first aspect of the present invention there isprovided a blast attenuation container, said container including anouter cover defining an internal cavity and an inner receptacle locatedin said internal cavity, said inner receptacle for containing one ormore items, said outer cover having access means for gaining access tothe inner receptacle and wherein at least said inner receptacle is linedwith or formed from at least one type of blast attenuation material,thereby minimising the effects of a blast from an explosive deviceplaced in said inner receptacle.

[0008] Preferably the inner receptacle minimises the lateral effects ofthe blast.

[0009] Preferably the inner receptacle is provided with an extensionportion covering the whole or a substantial part of an upper surface ortop of the inner receptacle. The extension portion can contact the uppersurface directly or be provided a spaced distance apart therefrom.

[0010] The extension portion can be provided with liquid suppressionmeans, liquid/air suppression means and/or an expansion chamber means.Any of these means can be used singly or in combination. The liquid actsto absorb the energy of the blast and can include water The water andair ratios can be varied to produce desired levels of protection. Theextension portion can also be lined with or formed from blastattenuation material.

[0011] Preferably the liquid in the extension portion is treated againstfungal and bacterial growth by using a fungicide, bactericide,sterilising solution/composition and/or the like.

[0012] Further preferably the liquid in the extension portion is treatedagainst freezing by using an anti-freeze.

[0013] The extension portion can be supported above the inner receptacleone or more supporting legs or by any other conventional supportingmeans. For example, the extension portion can be supported by attachmentmeans between the inner receptacle and/or the outer cover.

[0014] The extension portion or top of the blast attenuation containeraccording to the present invention can be retrofitted to a conventionalcontainer or litter bin.

[0015] Since the corners and edges of an object are susceptible to theconcentration of stress and crack initiation, these areas are mostaffected by the force of a blast. It is therefore preferable to minimisethe number of edges and corners of the inner receptacle and outer cover,for example a substantially cylindrical receptacle and outer cover canbe used.

[0016] Preferably the expansion chamber is spherical or oval in shape.Alternatively the expansion chamber can be substantially cylindrical inshape.

[0017] The inner receptacle can be made from over wrapped glass wovenrovings in a matrix of resin, such as epoxy resin. Alternatively, theglass woven rovings are formed by proper filament winding, which createsgreater hoop strength for the same weight of material used.

[0018] The blast attenuation material used to line the inner receptacleand/or extension portion/top is preferably resin particulate material.This material is typically porous. The outer cover can also be linedwith a blast attenuation material if required or it can simply be anaesthetic cover.

[0019] Preferably the outer cover is cylindrical and has a dome shapedtop portion to prevent items from being placed on top of the same. Thetop portion can have one or more access ports for the posting of itemsinto the inner receptacle. The top portion is dome shaped and the accessports are preferably cylindrical to minimise the number of edges andcorners which can undergo damage following a blast.

[0020] Preferably the outer cover is lightweight and frangible.

[0021] Preferably the outer cover has one or more advertising spacesprovided thereon.

[0022] The top portion can be integrally formed with the outer cover orit can be non-integral and detachably attached using fastening orlocking means.

[0023] Further preferably one or more access ports having internallyfitted closure flaps are provided in the Outer cover, top portion and/orinner receptacle. The closure flaps can be the same size as the accessports but preferably the flaps are oversized compared to the size of theaccess ports they are protecting. The flaps can be attached by anyconventional attachment means such as hinges or a sliding mechanism.

[0024] In one embodiment the outer cover helps to minimise the effect ofa blast, in addition to, or as an alternative to the inner receptacle.For example, the outer cover can be lined with blast attenuationmaterial

[0025] Preferably the blast attenuation container is provided withmovement means for moving the inner receptacle into and out of theinternal cavity defined by the outer cover via the access means. Themovement means allows lateral movement of the inner receptacle from theouter cover, thereby minimising the movement and disturbance to thecontents of the inner receptacle compared to lifting the innerreceptacle vertically from the outer cover.

[0026] The movement means also has the advantage of allowing thecontents of the inner receptable to be removed and or items to belocated therein, remotely without direct contact with the receptacle orwith reduced physical contact with the receptacle. Control means can beprovided to operate the receptacle remotely.

[0027] Preferably the movement means includes a roller or slide assemblyfor providing the lateral movement. The assembly comprises frame meansof sufficient strength to support the weight of the inner receptacle,empty or full, and to withstand frequent use. The inner receptacle isslidably located in or on the frame means.

[0028] The frame means are mounted on a supporting plinth or base of thecontainer. The supporting plinth can be made from bomb attenuationmaterial such that in the event of an explosion, the downward dynamicloading caused by the blast is mostly taken up by the bomb attenuationmaterial. This has the effect of reducing the amount of energytransmitted to the ground and thereby minimising the effects of theblast.

[0029] Preferably the access means via which the inner receptacle isremoved from the outer cover is separate from the one or more otheraccess ports for locating items in the inner receptacle.

[0030] Further preferably the access means for the inner receptacleremovable is located on a sidewall of the outer cover.

[0031] Additional security features can be used on the container. Forexample, locking devices could be used on one or all of the accessports.

[0032] The container can be a litter bin, post box, explosives orpyrotechnic container and/or the like.

[0033] Embodiments of the present invention will now be described withreference to the accompanying figures wherein:—

[0034]FIG. 1 is a perspective view of an inner receptacle of a blastattenuation litterbin according to an embodiment of the presentinvention;

[0035]FIG. 2 is a perspective view of an inner receptacle with anextension portion according to an embodiment of the present invention;

[0036]FIG. 3 is a perspective view of a blast attenuation litterbinaccording to an embodiment of the present invention;

[0037]FIG. 4 is a perspective view of the blast attenuation litterbinillustrating the movement means of the bin;

[0038]FIG. 5a is a perspective view of a portion of the inner receptaclemovement means when in a closed position;

[0039]FIG. 5b is a perspective view of a portion of the inner receptaclemovement means when in a partially open position;

[0040]FIG. 5c is a perspective view of a portion of the inner receptaclemovement means when in a fully open position;

[0041]FIG. 6 is an exploded view of a roller/slider assembly for usewith the inner receptacle movement means according to the presentinvention;

[0042]FIG. 7a is a perspective view of a litterbin according to afurther embodiment of the present invention;

[0043]FIG. 7b is a perspective view of the litterbin in FIG. 7a when theinner receptacle is in an open position;

[0044]FIG. 7c is a perspective view of the litterbin of FIG. 7a with theinner receptacle in a closed position.

[0045] Referring firstly to FIG. 1, there is illustrated an innerreceptacle or tub 2 for the containment of litter. The inner rub islined with blast attenuation material 4 and is located on a supportplinth 6 which also comprises blast attenuation material. Movement meansin the form of a roller/slider mechanism 8, which forms part of an innerrub extraction device, is mechanically attached to a base 10 of the tub2. The roller/slider mechanism 8 is also mounted on support plinth 6.

[0046] An extension portion 12 is provided which has a top section 14covering the top 16 of the inner tub 2, as illustrated in FIG. 2. Theextension portion 12 has a plurality of supporting legs 18, which arespaced a sufficient distance apart to allow the inner tub 2 to be movedbetween the same.

[0047] The extension portion 12 is also provided with a number of accessports 20 through which litter can be posted such that it falls into theinner tub 2. The access ports 20 are provided with oversized flaps (notshown), which are mounted on the inside of the extension portion 12,thereby preventing the flaps and/or contents of the tub from beingforced out of the access ports in the event of a blast.

[0048] The extension portion can be provided with water suppressionmeans, water/air suppression means and/or an expansion chamber. Thewater and air ratios can also be varied to produce desired levels ofprotection. The water can be replaced by another liquid if desired. Thewater or other liquid attenuates the force/energy of a blast.

[0049] Referring to FIG. 3, there is illustrated an outer cover 22 for alitterbin which defines an internal cavity 23 in which the inner tub 2and extension portion 12 are located.

[0050] The outer cover 22 comprises a dome shaped top portion 24 andcylindrical sidewalls 26. The dome portion 24 has access ports 28, whichcorrespond to the size and position of the access ports 20 in theextension portion 12, for the posting of litter into the inner tub 2.Access ports 28 can be provided with oversized flaps (not shown) in asimilar manner to the access ports 20. The flaps can be attached by aconventional hinge or sliding mechanism and are a close fit with theaccess ports in order to prevent blast emission through the same. Theflaps can also comprise security devices by which they can be locked toprevent unwanted packages being placed through them if the bins are in ahigh risk bomb threat area.

[0051] A further access port 30 is provided in sidewall 26 to allow theinner tub 2 to be extracted from the outer cover via sliding of the samealong the roller/slider mechanism 8, as illustrated in FIG. 4. The innertub can then be emptied and bin liners can be fitted or removed.

[0052] The opening of access port 30 and operation of the inner tubextraction device can be performed manually or by automated controlmeans. For example a bomb disposal robot or EOD could be used.

[0053] The dome 24 is shaped accordingly to prevent litterbags orpackages being placed on top of the outer cover. However, the dome canbe reshaped to provide flat sections along the sides to provideadvertisement space. The dome can be integral with the sidewalls 26 orit can be non-integral and fastened or locked in position.

[0054] Referring to FIGS. 5a-c and 6, there is illustrated aroller/sliding mechanism 8 which forms the movement means for extractionof inner tub from the outer cover in a lateral direction. Theroller/sliding mechanism 8 comprises a top section 30 which is bolted tothe base 10 of the inner tub 2, a bottom section 32 which is bolted intothe support plinth 6 via base plate 34 and a central slider unit 36which has a number of rollers 38 acting as a sliding interface betweentop section 30 and bottom section 32. It is noted that any otherconventional slide/roller mechanism could be used. For example, theinner tub can include rollers on the base thereof slidably located onframe means provided on the support plinth. The frame means can includetelescopic arms which allow the tub to be moved from a closed binposition within the outer cover to an open bin position outside theouter cover.

[0055] Referring to FIGS. 7a-7 c, there is illustrated a furtherembodiment of an inner tub 102 for the containment of litter. The innertub is lined with blast attenuation material 104 and the tub is locatedon a support plinth 106.

[0056] An inverted channel 108 is provided on the base of the inner tuband houses a wheel 110, typically made of rubber. The wheel 110 allowsthe tub to be moved in and out of an outer cover 112.

[0057] An expansion chamber 114 is provided above the inner rub andcomprises an access port 116 and a water/liquid chamber 118 above theaccess port 117 contained within the outer cover 112. The water/liquidchamber 118 contains a plurality of air pockets therein, typicallyprovided by bubble wrap or similar.

[0058] The inner tub 102 and expansion chamber 114 can be made from thesame moulding and be supported within the outer cover via tworectangular support sections. The support sections provide the points ofattachment for the hinges of the outer cover door and door lock.

[0059] The bomb attenuation material which lines inner tub 2 ispreferably porous, particulate resin material. For example, a materialsuch as TABRE could be used. Lining the cylinder with blast attenuationmaterial has been shown to reduce the force of the blast by 30%. Thethickness of the material within the inner tub can be altered accordingto where the greatest need for absorption of energy created by theblast. For example, the material can be of greater thickness around thefloor/sidewall interface. Both the material and inner tub can be X-Raytransparent, thereby allowing the same to be inspected for a suspectdevice. Inspection can occur both when the inner tub is locked in theouter cover and when it is extended from the outer cover.

[0060] The expansion portion or top can be lined with bomb attenuationmaterial and can be used in combination with a conventional bin or witha litterbin according to the present invention.

[0061] The components of the litterbin are cylindrical where possible.However, other shaped components can be used.

[0062] The outer covers can be coloured and designed in a variety ofways to make them blend in more effectively in a particular environment.The outer cover can also be lined with bomb attenuation material ifrequired but it is preferable for the outer cover to be lightweight andfrangible. For example, the outer cover can be made from moulded plasticor lightweight glass Fibre. This means that in the event of a blastthere is no high energy jagged fragments projected laterally

[0063] The inner tub can be made from over wrapped or filament woundglass woven rovings in a matrix of resin such as epoxy resin.

[0064] The liquid in the expansion portion can be treated withfungicides or the like to prevent bacterial/fungal growth in the same.In addition, the liquid can be treated with antifreeze to prevent thesame from freezing.

[0065] Thus the present invention provides an improved inexpensivecontainer which is capable of reducing both the lateral and verticaleffects of a blast caused by an explosive device location therein.

1. A blast attenuation container, said container including an outercover defining an internal cavity and an inner receptacle located insaid internal cavity, said inner receptacle for containing one or moreitems, said outer cover having access means for gaining access to theinner receptacle and wherein at least said inner receptacle is linedwith or formed from blast attenuation material, thereby minimising theeffects of a blast from an explosive device placed in said innerreceptacle.
 2. A blast attenuation container according to claim 1wherein the inner receptacle is provided with an extension portioncovering the whole or a substantial part of an upper surface or top ofthe inner receptacle.
 3. A blast attenuation container according toclaim 2 wherein the extension portion contacts the upper surface of theinner receptacle.
 4. A blast attenuation container according to claim 2wherein the extension portion is spaced a pre-determined distance apartfrom the upper surface of the inner receptacle.
 5. A blast attenuationcontainer according to claim 2 wherein the extension portion is linedwith or formed from blast attenuation material.
 6. A blast attenuationcontainer according to claim 2 wherein the extension portion is providedwith any or any combination of liquid suppression means, liquid/airsuppression means and/or an expansion chamber.
 7. A blast attenuationcontainer according to claim 6 wherein liquid provided in the extensionportion contains an antifreeze composition/solution.
 8. A blastattenuation container according to claim 6 wherein liquid provided inthe extension portion contains any or any combination of a fungicide, abactericide and/or a sterilising composition/solution.
 9. A blastattenuation container according to claim 2 wherein the extension portionis supported on or above the upper surface of the inner receptacle byone or more supporting legs.
 10. A blast attenuation container accordingto claim 2 wherein the extension portion is supported on or above theupper surface of the inner receptacle by attachment means locatedbetween the outer cover and the extension portion.
 11. A blastattenuation container according to claim 1 wherein movement means areprovided for laterally moving the inner receptacle in and/or oat of theinternal cavity via the access means.
 12. A blast attenuation containeraccording to claim 11 wherein the movement means includes aroller/slider assembly.
 13. A blast attenuation container according toclaim 12 wherein the roller/slidable assembly comprises frame means onwhich the inner receptacle is slidably located.
 14. A blast attenuationcontainer according to claim 13 wherein the frame means includestelescopic arms.
 15. A blast attenuation container according to claim 13wherein the frame means are mounted on a support base in or forming partof the outer cover.
 16. A blast attenuation container according to claim15 wherein the support base is made from blast attenuation material. 17.A blast attenuation container according to claim 11 wherein controlmeans are provided for operating the movement means remotely.
 18. Ablast attenuation container according to claim 1 wherein the innerreceptacle, extension portion and/or outer cover are substantiallycylindrical in shape.
 19. A blast attenuation container according toclaim 2 wherein the extension portion is substantially spherical or ovalin shape.
 20. A blast attenuation container according to claim 1 whereinthe inner receptacle is formed from over wrapped or filament wound glasswoven rovings in a matrix of resin.
 21. A blast attenuation containeraccording to claim 1 wherein the blast attenuation material is a resinbonded particulate material.
 22. A blast attenuation container accordingto claim 1 wherein the outer cover is provided with a top portion whichis detachably attached to the outer cover.
 23. A blast attenuationcontainer according to claim 1 wherein one or more access ports areprovided in the outer cover, extension portion, top portion, and/orinner receptacle for locating one or more items in said innerreceptacle.
 24. A blast attenuation container according to claim 23wherein closure flaps are provided over said access ports and saidclosure flaps are attached to an internal surface of the outer cover.25. A blast attenuation container according to claim 1 wherein thecontainer is any of a litter bin, an explosives or pyrotechnic containeror a letter box.
 26. A blast attenuation litter bin, said litter binincluding an outer cover defining an internal cavity and an innerreceptacle located in said internal cavity, said inner receptacle forcontaining one or more items, said outer cover having access means foraccessing the inner receptacle and wherein at least said innerreceptacle is lined with or formed from blast attenuation material,thereby minimising the effects of a blast from an explosive deviceplaced within said inner receptacle.